The production of a palatable dosage form is very important for patient compliance. The masking of unpleasant tastes is therefore an important consideration in the formulation of many therapeutic agents and is achieved by minimizing direct contact between the active species and the taste receptors in the buccal cavity of the subject .
Cationic copolymers synthesized from dimethylaminoethyl methacrylate and neutral methacrylic acid esters such as Eudragit E 100 have been employed in various taste-masking formulations. For instance, U.S. Pat. No. 5,275,823 discloses a chewable tablet comprising a granulate of a histamine H2-receptor antagonist and optionally Eudragit E 100 and an admixture of a taste-masking extragranular water-insoluble hygroscopic excipient. While the purpose of the extragranular water-insoluble hygroscopic excipient is to reduce or eliminate the intensely bitter taste, Eudragit E 100 can be included in the granulate to provide extra taste-masking properties. Examples show a ratio of Eudragit E 100 to drug of 1 to 10.
U.S. Pat. No. 5,489,436 discloses a chewable medicament tablet comprising a medicament coated with a taste-masking amount of a polymer blend of dimethylaminoethyl methacrylate and neutral methacrylic acid esters and a polymer selected from cellulose acetate and cellulose triacetate. This coating blend is intended to achieve a balance between taste masking, dissolution and rate of bioavailability.
U.S. Pat. No. 4,708,867 discloses a mini pellet dosage form of prednisone comprising a nonpareil seed coated with a first layer of the drug and a second layer of a copolymer of dimethylaminoethyl methacrylate and methyl methacrylate.
U.S. Pat No. 5,013,557 discloses a spray-dried spheroidal microcapsule comprising 1-70 wt% sucralphate and 30-99 wt % of a polymer soluble in gastric fluids such as maltrin. The examples illustrate 1:1 sucralfate to maltrin microcapsules, which can be incorporated in chewable products.
U.S. Pat. No. 4,760,093 discloses a taste neutral powder form of spray-dried acetaminophen which consists essentially of about 60% to 74% by weight acetaminophen and about 26% to 40% by weight of a copolymer, cationic in character, based on dimethyaminoethyl methacrylate and neutral methacrylic acid esters.